1. Field of the Invention
This invention relates to a writing instrument wherein a refill may be projected and retracted by shaking the writing instrument.
2. Description of the Prior Art
Heretofore, a variety of knocking type writing instruments wherein a refill is projected from its outer cylinder at the time of using such writing instruments have been proposed. In any instruments of this type, however, it is required to knock a knocking portion of such writing instruments by the user, and this inevitably results in changing the manner of holding the writing instrument so that another motion is required for obtaining such a state wherein writing preparations are ready.